Re: how to get average of matrices' elements?

The first time through your nested for loops, @m_avrg is uninitialized. You can uninitialized with:

my @m_avrg;
for my $i ( 0 .. 2 ) {
    $m_avrg[$i] = [ map { $_ = 0 } 1 .. 3 ];
#    $m_avrg[$i] = [ map { $_ => 0 } 1 .. 3 ]; # WRONG!
}
[download]

UPDATE: I copy'n'pasted the wrong code originally. Yes, Anon's x operator is better.

Use 4 single spaces for each level of indentation.

Comment on Re: how to get average of matrices' elements? Download Code

Replies are listed 'Best First'.
Re^2: how to get average of matrices' elements? by Anonymous Monk on Nov 30, 2016 at 19:07 UTC
That map is wrong, we're not building a hash. Just use `$m_avrg[$i] = [ (0) x 3 ];`	[reply]
Re^3: how to get average of matrices' elements? by toolic (Bishop) on Nov 30, 2016 at 19:13 UTC
That map is wrong, we're not building a hash. Please try running my code before you make such a claim. My code creates an array-of-arrays data structure with all elements initialized to 0. UPDATE: see my updated code.	[reply]
Re^4: how to get average of matrices' elements? by Anonymous Monk on Nov 30, 2016 at 19:39 UTC
I did run your code. Here's the output from Data::Dump: `[[1, 0, 2, 0, 3, 0], [1, 0, 2, 0, 3, 0], [1, 0, 2, 0, 3, 0]]`	[reply] [d/l]
Re^2: how to get average of matrices' elements? by Anonymous Monk on Nov 30, 2016 at 19:10 UTC
Also, another way to avoid the "uninitialized variable" warning is to use the += operator. `instead of this: $m_avrg[$a][$b] = ($m_avrg[$a][$b] + $list[$a][$b]); use this: $m_avrg[$a][$b] += $list[$a][$b];` [download]	[reply] [d/l]


We don't bite newbies here... much
	PerlMonks